This invention relates generally to the field of medical diagnostics, and more particularly to a non-invasive test for gastric acid secretion based upon the reaction of an orally administered substance which reacts with gastric acid, and in which hydrogen gas thus evolved is detected in exhaled air and belches and quantitatively related to the amount of acid in the stomach.
Gastric acid secretion is important in several disease conditions. Elevated basal levels are seen with the Zollinger-Ellison syndrome and decreased levels are seen in pernicious anemia and in some patients with gastric carcinoma. Hypochlorhydria predisposes to infectious diarrhea (1), (2), (3), (4), especially those due to Vibrio Cholera and Escheriachia coli. Drugs are commonly used in peptic ulcer disease to block or neutralize gastric acidity, (5), (6), although they are generally used without documenting the physiological effectiveness in the individual patient.
In the prior art, the measurement of gastric acid secretion has involved the placing of a tube in the stomach, and suctioning gastric contents for approximately two hours. Acid secretion is stimulated during this procedure with a subcutaneous injection of betazole or pentagastrin. Measurement of acid in the specimen is time consuming for the technician, and hence expensive. Because of the discomfort to the patient the need for careful specimen collection, the time involved and the expense, the test is rarely carried out except for hospitalized patients.